Datatypes for DTDs Submission: W3C Staff Comment

During this transitional period of the W3C
XML Activity while the XML
Schema Working Group develops and deploys their work, this submission provides a valuable mechanism for addressing the lack of data types such as integer, date, etc. in XML 1.0 DTD syntax in a way that is compatible with legacy systems.

However, it relies on a global convention for the interpretation of the
unqualified names e-dtype and a-dtype, while use of
XML Namespaces would make this
unnecessary; using the example from section 1. Datatype Declarations, this
might look like:

where the choice of dt4dtd as the namespace prefix is arbitrary
and can be changed on a per-use basis to avoid collisions with all other
names in the DTD.

The use of notations to declare datatypes is quite reasonable given the intended
use, but note that the system identifiers such as
urn:schemas-microsoft-com:datatypes/int in section 2.2 XML-Data datatypes use an unregistered URN namespace id,
schemas-microsoft-com (c.f.
URN Syntax (RFC 2141) and
URN Namespace Definition
Mechanisms (RFC 2611)). As of 13 Nov 1999, Microsoft published
documentation on those URNs at http://msdn.microsoft.com/xml/xmlguide/schema-datatypes.asp but they no longer service that address.